<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

{#  css  #}
    {% block extcss %}
    {% endblock %}

</head>
<body>

    <h2>父模板</h2>
    <hr>

    {% block head %}
    {% endblock %}
    <hr>

    {% block content %}
        <button>我是Content父模板中的按钮</button>
    {% endblock %}
    <hr>

    {% block foot %}
    {% endblock %}

{#  js  #}
    {% block extjs %}
    {% endblock %}

</body>
</html>